Push button electric snap switch



' A. DOUGLAS SH BUTTON ELECTRIC SNAP SWITCH Filed May 31, 1934 //v7-0/? HARRY A. DOUGL'A 5 BY 43 Patented Oct. 5, 1 937 PATENT OFFICE rusn nu'r'rou anaemic, SNAP swrron Harry A. Douglas, Bronson, Mich, assignor to Kingston Products Corporation, a corporation of Indiana Application May 31, 1934, Serial No. 728,283

13 This invention relates to improvements in electric switches and more particularly to a snap ac-.

invention with the understanding that minor detail changes may be made without departing from the scope thereof.

.In the drawing-- Figure 1 is a view in central vertical section of an embodiment of this invention, with'parts illustrated in elevation. I l

Figure 2 is a similar view in section taken at right angles to Figure 1.

Figure 3 is a view similar to Figure 1, with parts broken away, illustrating the position ;of the circuit making and breaking mechanism just before the circuit is broken, andindicating how a third terminal can be embodied thereon.

Figure l is a detail view in section'taken on the line 4-4, Figure 1.

. Figure 5 is a detail view in section taken on the line5--5, Figure 3. V I V Figure 6 is a view in reduced scale in section taken on the line 6--6, Figure 1. 1

As illustrated in Figures 1, 2, and 3, the switching mechanism is enclosed in a cup-shaped me-' tallic cylindrical casing I having the end closure 2 provided with a central circular opening 3 for the reception of a shouldered push button Q of insulating material having a flange 5 upon the bottom thereof to engage the inner side of the closure- 2 to prevent the button 4 from passing therethrough, as shown. The under side of the button is provided with an axial recess 6 for a. purpose hereinafter described.

The open end ofthc casing l is closed by a contact carrying disc I of insulating material which is held securely in position by a plurality of spaced apart fingers 8, preferably three in number, forming integral extensions of the casing wall which are passed through corresponding notches 9 in the periphery of the dim i and then a bent overthe outer surface of the disc to hold 50 the same firmly against the end of the casing wall. The contact carrying disc I mountstwo electric terminals III and Ii, preferably of the snap terminal type disclosed in this applicant's prior copending application, Serial 110."!131113, 55 filed March 2, 1 934, adapted to be electrically which illustrates a preferred embodiment of this connected to electric conductors, not shown, upon the outer side of the disc I. As shown, each terminal includes a rectangularblock having a cylindrical extension which extensions are preferably reduced in diameter. When this type terminal is employed, it is desirable to provide the carrier disc .I with circular apertures through which the reduced extremities of the terminals are passed and the metal of the end is then expanded or riveted upon the interior of the disc I to hold the terminals in place. The terminals Ill and Ii are mounted perpendicularly to the discat equal distances from the center.

1 The center of the contact carrying disc I is provided with an integral rectangular projection I of insulating material upon its inner surface having sides perpendicular to the upper surface of the disc with the side adjacent the. terminal i joined to an upwardly extending angular surface l3 terminating in a flatcentral transverse portion ll. An'electriccontact IS in the form of a metallic strip is connected to the terminal Ill, preferably by passing the reduced cylindrical portion thereof through an aperture provided therefor in the end of said strip, upon the outer side of the contact carrying disc. The other end of the strip is then passed through the disc I to embrace the adjacent side and angular surface l3 of the central projection I upon. the inner side of the disc I with the upper surface of the strip terminating flush with the flat top of the central transverse portion I4. The upper surface of the insulating projection leading .from the flat top of-the transverse portion ll opposite the contactstrip I is continued downwardly therefrom at 35 an angle similar to that formed by the upper surface of said strip for a similar distance and then I curved upwardly to form a stop l6, fora purpose hereinafter described. The expanded or riveted head of the terminal III is preferably received in a recess provided therefor upon the inner surface of the disc I to be wholly received below that surface, for a purpose hereinafter described.

The switching. mechanism is carried upon a U-shaped metallic bracket having a. rectangular base i'l with a. central cut out portion it, cut out to receive the projection I of the disc i, providing end portions i 9, one of which extends over the countersunk expanded end of the terminal l0 and having the sides of the base ll provided with integral outstanding perforated ears Eli and ii. The reduced cylindrical portion of the terminal I] is passed through the apertured ear it with the end expanded or riveted upon the upper surface thereof while the other ear M is secured tion IQ of the base extending over the terminal I 6 is spaced apart from the contact l and the opposite end portion I9 is in engagement with the wall l2 of the central projection I of the disc 1.

' of housing are provided with transverse One of the end portions I9 is provided upon its inner side with an integral upwardly extending stop 23 bent back at an angle and spaced apart from the contact 15 to form a stop complementar y to the stop I 6 of the insulated projection I.

The ear bearing sides of the base are extended upward to form two similar arms 24 perpendicular to the base I! and equally spaced from the axis of the casing I with each side of each arm provided midway its height with inwardly extending integral fingers 25. The switching device for alternately continuing the circuit from the terminal II to the contact |5 of the terminal I6 is mounted to oscillate upon a pivot 26 passing through apertures in the upper ends of the arms 24. The circuit making and breaking mechanism includes an oscillating actuator A- caused to oscillate by an oscillating operator 0.

The actuator A is mounted upon the pivot pin 26 passed through apertures in the arms 24 of the supporting bracket and includes two similar metallic actuating plates 21 adapted to receive the pivot pin 26 and depend therefrom in sliding engagement with the respective arms 24 of the supporting bracket and terminating short of the high point of the carrier disc projection I with a portion of the opposite longitudinal sides struck up at right angles to the main body to form right angular flanges 28 extending upward from the bottom leaving oppositely disposed similar outstanding arms 29 extending from the .body of the plate, the longitudinal edges of the flanges 28 v being adapted to engage the similar edges of the corresponding flanges on the respective plates 21. The actuator plates 21 are mounted upon the pivot pin 26 in similar longitudinally elongated bearings 36 allowing a sliding lonm'tudin'al movement ofthe plates about the pin 26. The upper surfaces of the actuator arms 29 lie in the same plane which passes slightly below the axis of the pivot pin 26 when the upper end of the bearing 36 is in contact with the upper surface of the pin 26. A sp ring housing 3| in the form of an inverted u is mounted between the plates 21 and embraced by the flanges 28. The extremities of the sides flanges 32 adapted to pass under the lower extremities of the actuator flanges 28 with the terminations thereof inclined upwardly to engage the outer sides of the oppositely disposed actuator flanges on each side of the housing and position the base or top of the housing at a distance below the lower end of the actuator bearing 36. The housing 3| receives in sliding engagement therewith a detent 33 in the form of a rectangular casing closed at the lower end in a rounded nose 34 and open at the other end to receive a coil spring.36 bearingagainst the interior of the nose and top of the housing. 1

The actuator A is caused to oscillate by the .movement of an oscillating operator- 0. The

oscillating operator 0 is preferably formed of a flat strip of metalcentrally struck up to form oppositely disposed similar angular flat surfaces 36 departing downwardly from its transverse center line terminating in upwardly extending tangential stops 31 with the opposite sides struck downwardly to form depending perforated ears;

meeting edge of the'surfaces 36 parallel with and in the same plane as'the axis of the pivot and with the upper surfaces of the actuator arms 29 in contact with the under surfaces of the tangential stops 3! when the lower ends of the bearings 36 of the actuator are in engagement with the under side of the pivot pin 26. When the bridge nose 34, actuator and operator have been assembled upon the supporting bracket, the fingers 25 of the bracket arms 24 are bent toward each other, as shown in Figure 2, to prevent the nose 34 from riding over the stop 23 of the base or the stop l6 of the projection I. Y

Back and forth movement is imparted to the oscillating operator by the manual depression of a reciprocating operator 33 preferably of insulating material and in the form of a flnger depending centrally from a body 46 extending transversely thereof with its top and bottom surfaces perpendicular to the center line of the finger 39 and with the top'surface of the body 46 in engagement with the top 4| of a frame received within recess 6 of the button 4. As shownin Figure 2, the frame includes sides 42 depending from eachside of the top 4| to embrace the longitudinal sides of the body 46, and are jutted to form shoulders 43, and then continued downwardly and away from each other,to join similar parallel portions 44 arranged equidistantly and parallel to the axis of the casing, with the lower portion of eachprovided with a central longitudlnal slot 45 adapted to receive an extension 46 of the pivot pin 26 of the actuator and oscillating operator. The operating finger 33 is normally maintained with its center line coincident with flat top 4| of the frame and the top 4| in engagement with the bottom of the recess 6 in the button 4 and the flange 6 thereof in engagement with the under surface of the casing closure 2. The lower end of the finger 36 is preferably pointed and in the position just described terminates short of the highest point of the angular surfaces 36 of the oscillating operator and is preferably guided above the transverse center thereof by extending the tops of the bracket arms 24 into inturned guiding flanges 48;

As shown in Figure 1, the top 4| of the frame is reduced in width and provided with curved edges 66 tangential to the under side thereof depression of the button'4 causes the flnger 36 to engage said surface and slide thereover to engage the stop 31 of the oscillating actuator and at the same time the top of the body 46 will move I the same side of the casing axis, whereby upon about the curved end 60 of the top of the frame as a fulcrum. Upon continued depression of the button 6, the pivoted operator finger 39 imparts a rotative movementto the oscillating operator and through the contact of the engaged stop 31 withthe adjacent actuator arm 29 bodily moves the actuator over its pivot 26 in the direction of the engaged stop 23 of the bridge nose-'34 until the upper end of the bearing 30 engages the upper side of the pin 26, placing the detent spring 35 under'greater tension than normal. As the button 4 continues downward, its movement is transmitted through the pivoted finger 39 to impart a rotative movement to the actuator about its upper bearing on the pivot 26 causing the detent nose. I

34 to travel over the upwardly inclined surface of the contact i towards its high point, as shown in Figure 3, holding the contact with the terminal liiclosed under a slightly increasing tension of the spring 35 as the nose approaches the high point of the contact. During this rotative movement the pivot pin 26 acts as the fulcrum of a bell cranklever with the power being applied upon one arm by the finger 39 at the point of 3 contact P between the oscillating operator end 31,

and the actuator arm 29. During this movement, the point of contact? moves. in the direction of the angular surface of the contact so that as the line from point P to the engaging point of the nose 3t approaches-a right angle to the angular portion of the contact IS, the friction of. the nose thereagainst is minimumized. The movement'of the nose 34 toward the high point of thecontact increases the tension of the spring 35 so that just before the nose reaches the high point, the spring 35 bodily moves the actuator away'from the contact i5 to bring the lower end of its bearing 30 into engagement with the under side of the pin 26 with the nose 34 still held in contact with the strip 15, and during this movement causes the actuator torotate about the point P as a pivot. In other words, during the application of power at P, the bell crank lever rotates about the pivot 26 as a fulcrum, but as the nose 34 approaches the high point of the contact l5, power is applied at the lower end of the other arm .of the bell crank lever causing it to rotate aboutthe point P as a fulcrum, the-elongated bearing 39 allowing sliding movement of the actuator about the fixed pivot 26. The movement imparted to the actuator by the stored up power in the spring 35 causes the nose 34 to snap over the ,high pointof the contact l5 and to quickly extend the nose 34 to engage the stop it on the other end of the insulation projection I and thereby quickly oscillate the nose 34 to break engagement 'with the contact of the terminal l0.

From the above, it is seen that as 'soon as the pivoted finger 39 has rotated the oscillating operator O sufficiently to shift the actuator A from its normal pivot 26 to its eccentric pivot P, the spring 35 automatically completes the oscillation to snap the nose 34 out of engagement with the contact strip i5 and thereby break the circuit from terminal Ii to terminal Ill. Upon release of the button 4, the spring 41 returns the button to the normal extended position, and the pivoted finger 39 is returned with its lower endabove the oscillating operator 0 in line with the axis of the casing i. The opposite sides of the oscillating operator 0, oscillating actuator and angular surfaces of projection I being similar, upon the next depression of the button, the end of the pivoted finger 39 will engage the opp ite side of the os clllatlng operator 0 to first depress and impart rotative movement to the actuator A from its normal to its eccentric pivot and snap the bridge nose to close the circuit.

This invention also contemplates its application to a two circuit switch, as shown in Figure 3. In this form, the insulating projection I carrying the contact strip II from the terminal Ill is'procit vided with a complementary oppositely disposed surface l3a upon which is mounted a contact strip Ilia, mounted upon the disc I and connected the adjacent contact strip iia andis provided.

with an upwardly extending stop 23a bent back at an angle similar to the corresponding stop it.

In this form, when the current continuing nose 34 is oscillated to break the circuit to the terminal It) just as soon as it is snapped over the flat insulating surface l4, it immediately'engages the contact strip lid to completethe circuit to the additional terminal and then slides over said contact strip until .it engages the stop 23a upon the end portion i9 of the metallic bracket, whereby upon manual depression oi the button t the re spective circuits from the terminal i i to the other terminals are each closed and opened alternatively.

As shown and described. the parts of this improved switching mechanism excepting the push '10 to a third terminal (not shown) in the same man- I button, operating finger and contact carrier are all adapted to be formed of metal stamping to be easily and quickly assembled. The operating parts are dependable and the spring 35 for imparting the snap movement is fully protected. and it the other parts are so constructed that the switch may be operated thousands of times without any of the parts deteriorating or getting' out of order. a I

gagement with its pivot and sliding engagement with the bridge, means maintaining the actuator in engagement with its pivot and with said bridge, means guided by the actuator pivot extending through the casing for manual reciprocation to oscillate the operator to engage and bodily move the actuator over, its pivot and then rotate the actuator to travel in sliding engagement with the bridge, and means to shift the axis of rotation of the actuator from its normal pivot to a pivotal point eccentric thereto and thereafter snap the bridge to make or break the circuit therethrough.

2. An electric switch including. a cup-shaped casing, a contact carrier mounted upon the open end thereof, a switching mechanism mounted on the contact carrier including a plurality of spaced apart contacts, agmetallic bracket electrically conneted to one of said contacts, a current continuing bridge mounted for back and forth movement to actuator having a sliding engagement with its pivot and sliding engagement with the bridge, means maintaining the actuator in engagement with its pivot and with said bridge, means mounted upon the bracket extending through the casing for manual reciprocation to oscillate the operator to engage and bodily move the actuator over its pivot and then rotate the actuator to travel in sliding engagement with the bridge, and means to shift the axis of rotation of the actuator from its normal pivot to a pivotal point eccentric thereto and thereafter snap the bridge to make or break the circuit.

3. The structure of claim 2 wherein the manually operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot.

4. The structure of claim 2 wherein the manually operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot and wherein a spring is interposed between the bracket and frame normally maintaining the frame in its extended position.

5. The structure, of claim 2 wherein the manu ally operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot and wherein the upper end of said frame mounts a shouldered push button of insulating material mounted for reciprocation in the casing.

6. The structure of claim 2 wherein the manually operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot and wherein the upper end of said frame mounts a shouldered push button of insulating material mounted for reciprocation in the casing closure-opposite the contact carrier.

7. The structure of claim 2 wherein the manually operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot and wherein the upper end of the frame pivotally mounts an operating finger to engage and impart a rotative movement. to the oscillating operator upon reciprocation.

-8. The structure of claim 2 wherein the manually operable means includes a frame embracing said bracket and guided for reciprocation by the actuator pivot and wherein the upper end of the frame pivotally mounts an operating finger to V engage and impart arotative movement to the oscillating operator upon reciprocation, and

, wherein a push button mounted for reciprocation in the casing closure is provided upon its inner surface with a recess to receive and embrace the upper endof the frame-to coact,with the top of the frame to pivot the operating finger.

9. The structure of claim 2 wherein the manually operable means includes a frame embracing. said bracket and guided for reciprocation by the actuator pivot, wherein the upper end of the frame pivotally mounts an operating finger to engage and impart a rotative movement to the oscillatingoperator upon reciprocation, and

' wherein a push button mounted'for reciprocation in the casing closure is provided p n its inner surface with a recessto receive and embrace the upper end of the frame to coact with the top of the frame to pivot the operating finger, and

wherein the lower portion of the finger received within the push button is provided with a fiat surface extending from each side perpendicular to the longitudinal center line of the finger and a compression spring is coiled about the finger with one end anchored upon the top of the bracket and the other end pressing upon said fiat surfaces to maintain the frame extended with the longitudinal center line of the finger and axis of the casing coincident. 10. An electric switch including, a cup-shaped casing, a contact carrier mounted upon the open end thereof, a switching mechanism mounted on the contact carrier including a plurality of spaced apart contacts, a central projection of insulating material upon the carrierhaving spaced apart oppositely disposed angular surfaces, a contact strip connected to one of the'contacts mounted on one of the angular surfaces, a metallic bracket surrounding the said projection electrically connected to one of said contacts, a current continuing bridge mounted for back and forth movement over said angular surfaces to make and break a circuit through the bracket from one contact to another alternately, an actuator mounted for oscillation about a pivot upon the bracket above the bridge, an oscillating operator mounted upon the actuator pivot having means to engage and oscillate the actuator, said actuator having a sliding engagement with its pivot and sliding engagement with the bridge, means maintaining the actuator in engagement with its pivot and said bridge in engagement witlfthe said projection, means mounted upon the bracket extending through the casing for manual reciprocation to oscillate the operator to engage and bodily move the actuator over its pivot and then rotate the actuator to travel in sliding engagement with the bridge. and means to shift the axis of rotation of the actuator from its normal pivot to a pivotal point eccentric thereto and thereafter snap the'bridge to make or break the circuit.

11. An electric switch including, a cup-shaped casing, a contact carrier mounted upon the open end thereof, a switching mechan sm mounted on the contact carrier including a plurality of spaced apart contacts, a central projection of insulating material. upon the carrier having spaced apart oppositely disposed angular surfaces, contact strips mounted on each of the angular surfaces,

a metallic bracket surrounding the said projection electrically connected to one of said contacts, a current continuing bridge mounted for back and forth movement over said projection and contacts thereon to make and break a circuit through the bracket from one contact to another alternately, an actuator mounted for oscillation about a pivot upon the bracket above the bridge, an oscillating operator-mounted upon the actuator pivot having means to engage and oscillate the actuator, said actuator having a sliding engagement with its pivot and'slidlng engagement with the bridge, means maintaining the actuatorin engagement with its-pivot and said bridge in' engagement with said projection or bracket extending through the casing for manual reciprocation to oscillate the operator to engage -a contact thereon, means mounted upon the I lever to eflect movement of said lever when said circuit through one or the other angular contacts.

12. An electric switch, comprising: a base; a casing, secured to said base, and having an opening in one of its walls; contacts canied by said base; a pivot structure, carried by said base, providing a pivot, and also having receiving means;

movable means, swingable about said pivot, and movable into and out of engagement with said contacts; alever swingable about said pivot, said lever and said movable means being so constructed and arranged that predetermined movement of said lever efiects movement of said movable means; a manually actuated operator, slidably extending through the opening in said casing and having an abutment engageable with the inner surface of the wall adjacent said opening, said operator having a slot directed towards the interior of said casing; a motion transmitting member, having a portion rockably received in said slot, and a portion adapted to engage said operator is moved inwardly of said easing; and resilient means, having one end disposed in the receiving means of said pivot structure, and having its other end'bearing against said rockably mounted portion of said motion transmitting member, said resilient means being so constructed and arranged to urge said operator abutment into engagement with the inner surface of the wall adjacent the opening in said casing, and also to urge said motion transmitting member to previding a pivot, and also having receiving means; movable means, swingable about said pivot, and movable into and out of engagement with said contacts; a lever swingable about said pivot,said lever and said movable means being so constructed and arranged that predetermined movement of said lever eiiects movement of said movable means; a manually actuated operator, slidably extending through the opening in said casing and having an abutment engageable with the inner surface of the wall adjacent said opening, said operator having a slot directed towards the interior of said casing; a bracket member, having a portion disposed, in said operator slot, said portion comprising spaced apart surfaces, and said bracket memberalso having legs provided with elongated slots, the margins of which engage said pivot to guide movement of said bracket and said operator; a motion transmitting member, having a portion rockably received between the spaced apart surfaces ofsaid bracket member and the adjacent part ofthe slot in said operator, and a portion adapted to engage said lever to effect movement of said lever when said operator is moved inwardly of said casing; and resilient means, having one end disposed in the receiving means of said pivot structure, and having itsv other end bearing against said rockably mounted portion of said motion transmitting member, said resilient -means being so constructed and arranged to urge said operator abutment. into en gagement with the inner surface or the wall adjacent the opening in said casing and also to determined relation with respect to said operator.

HARRY A. DOUGLAS.

' urge said motion transmitting member to pre- 

